diff --git a/tests/integration/update_cluster/additionalobjects/kubernetes.tf b/tests/integration/update_cluster/additionalobjects/kubernetes.tf
index a4824ba9d9..358a826b7e 100644
--- a/tests/integration/update_cluster/additionalobjects/kubernetes.tf
+++ b/tests/integration/update_cluster/additionalobjects/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.additionalobjects-example-com.cidr_block
   vpc_id                       = aws_vpc.additionalobjects-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.additionalobjects-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/apiservernodes/kubernetes.tf b/tests/integration/update_cluster/apiservernodes/kubernetes.tf
index 56c3ed2621..a300385213 100644
--- a/tests/integration/update_cluster/apiservernodes/kubernetes.tf
+++ b/tests/integration/update_cluster/apiservernodes/kubernetes.tf
@@ -19,7 +19,7 @@ locals {
   vpc_cidr_block                  = aws_vpc.minimal-example-com.cidr_block
   vpc_id                          = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block             = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length            = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length            = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "apiserver_autoscaling_group_ids" {
@@ -103,7 +103,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/aws-lb-controller/kubernetes.tf b/tests/integration/update_cluster/aws-lb-controller/kubernetes.tf
index b59b3a10b2..86a878321e 100644
--- a/tests/integration/update_cluster/aws-lb-controller/kubernetes.tf
+++ b/tests/integration/update_cluster/aws-lb-controller/kubernetes.tf
@@ -25,7 +25,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -133,7 +133,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/bastionadditional_user-data/kubernetes.tf b/tests/integration/update_cluster/bastionadditional_user-data/kubernetes.tf
index 5eecad6d4c..1dfa4875cf 100644
--- a/tests/integration/update_cluster/bastionadditional_user-data/kubernetes.tf
+++ b/tests/integration/update_cluster/bastionadditional_user-data/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.bastionuserdata-example-com.cidr_block
   vpc_id                            = aws_vpc.bastionuserdata-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.bastionuserdata-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/cluster-autoscaler-priority-expander-custom/kubernetes.tf b/tests/integration/update_cluster/cluster-autoscaler-priority-expander-custom/kubernetes.tf
index e019b1bfdd..136fa002b3 100644
--- a/tests/integration/update_cluster/cluster-autoscaler-priority-expander-custom/kubernetes.tf
+++ b/tests/integration/update_cluster/cluster-autoscaler-priority-expander-custom/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.cas-priority-expander-custom-example-com.cidr_block
   vpc_id                       = aws_vpc.cas-priority-expander-custom-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.cas-priority-expander-custom-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/cluster-autoscaler-priority-expander/kubernetes.tf b/tests/integration/update_cluster/cluster-autoscaler-priority-expander/kubernetes.tf
index 9dcd00d8d2..f5ad26fb39 100644
--- a/tests/integration/update_cluster/cluster-autoscaler-priority-expander/kubernetes.tf
+++ b/tests/integration/update_cluster/cluster-autoscaler-priority-expander/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.cas-priority-expander-example-com.cidr_block
   vpc_id                       = aws_vpc.cas-priority-expander-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.cas-priority-expander-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/complex/kubernetes.tf b/tests/integration/update_cluster/complex/kubernetes.tf
index b082ac0b5f..618ce05504 100644
--- a/tests/integration/update_cluster/complex/kubernetes.tf
+++ b/tests/integration/update_cluster/complex/kubernetes.tf
@@ -18,7 +18,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.complex-example-com.cidr_block
   vpc_id                            = aws_vpc.complex-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.complex-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -98,7 +98,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/compress/kubernetes.tf b/tests/integration/update_cluster/compress/kubernetes.tf
index 4cf46da003..ecea8614f7 100644
--- a/tests/integration/update_cluster/compress/kubernetes.tf
+++ b/tests/integration/update_cluster/compress/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.compress-example-com.cidr_block
   vpc_id                       = aws_vpc.compress-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.compress-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/containerd-custom/kubernetes.tf b/tests/integration/update_cluster/containerd-custom/kubernetes.tf
index e8359f42fc..cf40737983 100644
--- a/tests/integration/update_cluster/containerd-custom/kubernetes.tf
+++ b/tests/integration/update_cluster/containerd-custom/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.containerd-example-com.cidr_block
   vpc_id                       = aws_vpc.containerd-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.containerd-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/containerd/kubernetes.tf b/tests/integration/update_cluster/containerd/kubernetes.tf
index e8359f42fc..cf40737983 100644
--- a/tests/integration/update_cluster/containerd/kubernetes.tf
+++ b/tests/integration/update_cluster/containerd/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.containerd-example-com.cidr_block
   vpc_id                       = aws_vpc.containerd-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.containerd-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/digit/kubernetes.tf b/tests/integration/update_cluster/digit/kubernetes.tf
index 91c2160717..31fa7e698f 100644
--- a/tests/integration/update_cluster/digit/kubernetes.tf
+++ b/tests/integration/update_cluster/digit/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                        = aws_vpc.prefix_123-example-com.cidr_block
   vpc_id                                = aws_vpc.prefix_123-example-com.id
   vpc_ipv6_cidr_block                   = aws_vpc.prefix_123-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                  = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                  = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/docker-custom/kubernetes.tf b/tests/integration/update_cluster/docker-custom/kubernetes.tf
index 6e5b51199a..3d8a0c5086 100644
--- a/tests/integration/update_cluster/docker-custom/kubernetes.tf
+++ b/tests/integration/update_cluster/docker-custom/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.docker-example-com.cidr_block
   vpc_id                       = aws_vpc.docker-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.docker-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/existing_iam/kubernetes.tf b/tests/integration/update_cluster/existing_iam/kubernetes.tf
index 68416bec87..07a8b577f1 100644
--- a/tests/integration/update_cluster/existing_iam/kubernetes.tf
+++ b/tests/integration/update_cluster/existing_iam/kubernetes.tf
@@ -13,7 +13,7 @@ locals {
   vpc_cidr_block               = aws_vpc.existing-iam-example-com.cidr_block
   vpc_id                       = aws_vpc.existing-iam-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.existing-iam-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -73,7 +73,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/existing_sg/kubernetes.tf b/tests/integration/update_cluster/existing_sg/kubernetes.tf
index 320e052474..f36c383b16 100644
--- a/tests/integration/update_cluster/existing_sg/kubernetes.tf
+++ b/tests/integration/update_cluster/existing_sg/kubernetes.tf
@@ -17,7 +17,7 @@ locals {
   vpc_cidr_block               = aws_vpc.existingsg-example-com.cidr_block
   vpc_id                       = aws_vpc.existingsg-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.existingsg-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -93,7 +93,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/external_dns/kubernetes.tf b/tests/integration/update_cluster/external_dns/kubernetes.tf
index 3a43e6d97a..5d09e440f5 100644
--- a/tests/integration/update_cluster/external_dns/kubernetes.tf
+++ b/tests/integration/update_cluster/external_dns/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/external_dns_irsa/kubernetes.tf b/tests/integration/update_cluster/external_dns_irsa/kubernetes.tf
index 45a0bf0680..c091c3f062 100644
--- a/tests/integration/update_cluster/external_dns_irsa/kubernetes.tf
+++ b/tests/integration/update_cluster/external_dns_irsa/kubernetes.tf
@@ -23,7 +23,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -123,7 +123,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/externallb/kubernetes.tf b/tests/integration/update_cluster/externallb/kubernetes.tf
index 305bc004ff..48bcb80632 100644
--- a/tests/integration/update_cluster/externallb/kubernetes.tf
+++ b/tests/integration/update_cluster/externallb/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.externallb-example-com.cidr_block
   vpc_id                       = aws_vpc.externallb-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.externallb-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/externalpolicies/kubernetes.tf b/tests/integration/update_cluster/externalpolicies/kubernetes.tf
index 66e7b0768a..7329f7f68b 100644
--- a/tests/integration/update_cluster/externalpolicies/kubernetes.tf
+++ b/tests/integration/update_cluster/externalpolicies/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.externalpolicies-example-com.cidr_block
   vpc_id                       = aws_vpc.externalpolicies-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.externalpolicies-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/ha/kubernetes.tf b/tests/integration/update_cluster/ha/kubernetes.tf
index c2da2f34d6..80865883aa 100644
--- a/tests/integration/update_cluster/ha/kubernetes.tf
+++ b/tests/integration/update_cluster/ha/kubernetes.tf
@@ -17,7 +17,7 @@ locals {
   vpc_cidr_block               = aws_vpc.ha-example-com.cidr_block
   vpc_id                       = aws_vpc.ha-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.ha-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -93,7 +93,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/irsa/kubernetes.tf b/tests/integration/update_cluster/irsa/kubernetes.tf
index a8a000ec23..1067f69107 100644
--- a/tests/integration/update_cluster/irsa/kubernetes.tf
+++ b/tests/integration/update_cluster/irsa/kubernetes.tf
@@ -23,7 +23,7 @@ locals {
   vpc_cidr_block                           = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                   = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                      = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                     = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                     = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -123,7 +123,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/karpenter/kubernetes.tf b/tests/integration/update_cluster/karpenter/kubernetes.tf
index ab17804a40..8aac18ca10 100644
--- a/tests/integration/update_cluster/karpenter/kubernetes.tf
+++ b/tests/integration/update_cluster/karpenter/kubernetes.tf
@@ -25,7 +25,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -133,7 +133,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/lifecycle_phases/network-kubernetes.tf b/tests/integration/update_cluster/lifecycle_phases/network-kubernetes.tf
index a39019d22b..acf30f11ef 100644
--- a/tests/integration/update_cluster/lifecycle_phases/network-kubernetes.tf
+++ b/tests/integration/update_cluster/lifecycle_phases/network-kubernetes.tf
@@ -8,7 +8,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.lifecyclephases-example-com.cidr_block
   vpc_id                            = aws_vpc.lifecyclephases-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.lifecyclephases-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -48,7 +48,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/many-addons-ccm-irsa/kubernetes.tf b/tests/integration/update_cluster/many-addons-ccm-irsa/kubernetes.tf
index 03138e4dbd..18d570c9cb 100644
--- a/tests/integration/update_cluster/many-addons-ccm-irsa/kubernetes.tf
+++ b/tests/integration/update_cluster/many-addons-ccm-irsa/kubernetes.tf
@@ -29,7 +29,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -153,7 +153,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/many-addons-ccm-irsa23/kubernetes.tf b/tests/integration/update_cluster/many-addons-ccm-irsa23/kubernetes.tf
index 9f8b2780ea..8975c5a645 100644
--- a/tests/integration/update_cluster/many-addons-ccm-irsa23/kubernetes.tf
+++ b/tests/integration/update_cluster/many-addons-ccm-irsa23/kubernetes.tf
@@ -29,7 +29,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -153,7 +153,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/many-addons-ccm-irsa24/kubernetes.tf b/tests/integration/update_cluster/many-addons-ccm-irsa24/kubernetes.tf
index 92d8de961e..aa1aa9049c 100644
--- a/tests/integration/update_cluster/many-addons-ccm-irsa24/kubernetes.tf
+++ b/tests/integration/update_cluster/many-addons-ccm-irsa24/kubernetes.tf
@@ -29,7 +29,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -153,7 +153,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/many-addons-ccm-irsa25/kubernetes.tf b/tests/integration/update_cluster/many-addons-ccm-irsa25/kubernetes.tf
index 92d8de961e..aa1aa9049c 100644
--- a/tests/integration/update_cluster/many-addons-ccm-irsa25/kubernetes.tf
+++ b/tests/integration/update_cluster/many-addons-ccm-irsa25/kubernetes.tf
@@ -29,7 +29,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -153,7 +153,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/many-addons-ccm-irsa26/kubernetes.tf b/tests/integration/update_cluster/many-addons-ccm-irsa26/kubernetes.tf
index 1dba09b74d..d833d2fd70 100644
--- a/tests/integration/update_cluster/many-addons-ccm-irsa26/kubernetes.tf
+++ b/tests/integration/update_cluster/many-addons-ccm-irsa26/kubernetes.tf
@@ -29,7 +29,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -153,7 +153,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/many-addons-ccm/kubernetes.tf b/tests/integration/update_cluster/many-addons-ccm/kubernetes.tf
index 01b7f73dbd..e28f59ea40 100644
--- a/tests/integration/update_cluster/many-addons-ccm/kubernetes.tf
+++ b/tests/integration/update_cluster/many-addons-ccm/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/many-addons/kubernetes.tf b/tests/integration/update_cluster/many-addons/kubernetes.tf
index 753114f363..7245bf0ec6 100644
--- a/tests/integration/update_cluster/many-addons/kubernetes.tf
+++ b/tests/integration/update_cluster/many-addons/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-1.23/kubernetes.tf b/tests/integration/update_cluster/minimal-1.23/kubernetes.tf
index 131a9c79ca..d55922b3ab 100644
--- a/tests/integration/update_cluster/minimal-1.23/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-1.23/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-1.24/kubernetes.tf b/tests/integration/update_cluster/minimal-1.24/kubernetes.tf
index 9f4dfba9c9..37d03374e9 100644
--- a/tests/integration/update_cluster/minimal-1.24/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-1.24/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-1.25/kubernetes.tf b/tests/integration/update_cluster/minimal-1.25/kubernetes.tf
index 9f4dfba9c9..37d03374e9 100644
--- a/tests/integration/update_cluster/minimal-1.25/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-1.25/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-1.26/kubernetes.tf b/tests/integration/update_cluster/minimal-1.26/kubernetes.tf
index 7c1130be56..15b317b6ee 100644
--- a/tests/integration/update_cluster/minimal-1.26/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-1.26/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-dns-none/kubernetes.tf b/tests/integration/update_cluster/minimal-dns-none/kubernetes.tf
index a3e1d39ef9..e31f03f138 100644
--- a/tests/integration/update_cluster/minimal-dns-none/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-dns-none/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-etcd/kubernetes.tf b/tests/integration/update_cluster/minimal-etcd/kubernetes.tf
index 4d58800cb4..06d07933d6 100644
--- a/tests/integration/update_cluster/minimal-etcd/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-etcd/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-etcd-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-etcd-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-etcd-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-gp3/kubernetes.tf b/tests/integration/update_cluster/minimal-gp3/kubernetes.tf
index 3ff0853d8d..5356b3bbb0 100644
--- a/tests/integration/update_cluster/minimal-gp3/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-gp3/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-ipv6-calico/kubernetes.tf b/tests/integration/update_cluster/minimal-ipv6-calico/kubernetes.tf
index 80f11ed7e1..43fdea07d9 100644
--- a/tests/integration/update_cluster/minimal-ipv6-calico/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-ipv6-calico/kubernetes.tf
@@ -22,7 +22,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.minimal-ipv6-example-com.cidr_block
   vpc_id                            = aws_vpc.minimal-ipv6-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.minimal-ipv6-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -118,7 +118,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-ipv6-cilium/kubernetes.tf b/tests/integration/update_cluster/minimal-ipv6-cilium/kubernetes.tf
index 9f5c4dbcce..d0853dbe0d 100644
--- a/tests/integration/update_cluster/minimal-ipv6-cilium/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-ipv6-cilium/kubernetes.tf
@@ -22,7 +22,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.minimal-ipv6-example-com.cidr_block
   vpc_id                            = aws_vpc.minimal-ipv6-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.minimal-ipv6-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -118,7 +118,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-ipv6-no-subnet-prefix/kubernetes.tf b/tests/integration/update_cluster/minimal-ipv6-no-subnet-prefix/kubernetes.tf
index a59b3f0b7f..ea952bd3e4 100644
--- a/tests/integration/update_cluster/minimal-ipv6-no-subnet-prefix/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-ipv6-no-subnet-prefix/kubernetes.tf
@@ -22,7 +22,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.minimal-ipv6-example-com.cidr_block
   vpc_id                            = aws_vpc.minimal-ipv6-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.minimal-ipv6-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -118,7 +118,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-ipv6/kubernetes.tf b/tests/integration/update_cluster/minimal-ipv6/kubernetes.tf
index b6fd0e0dbd..9c3f178110 100644
--- a/tests/integration/update_cluster/minimal-ipv6/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-ipv6/kubernetes.tf
@@ -22,7 +22,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.minimal-ipv6-example-com.cidr_block
   vpc_id                            = aws_vpc.minimal-ipv6-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.minimal-ipv6-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -118,7 +118,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-longclustername/kubernetes.tf b/tests/integration/update_cluster/minimal-longclustername/kubernetes.tf
index 1385bb84fc..11a5c9342f 100644
--- a/tests/integration/update_cluster/minimal-longclustername/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-longclustername/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.this-is-truly-a-really-really-long-cluster-name-minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.this-is-truly-a-really-really-long-cluster-name-minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.this-is-truly-a-really-really-long-cluster-name-minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal-warmpool/kubernetes.tf b/tests/integration/update_cluster/minimal-warmpool/kubernetes.tf
index ebc2f94348..197519aee3 100644
--- a/tests/integration/update_cluster/minimal-warmpool/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal-warmpool/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-warmpool-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-warmpool-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-warmpool-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal/kubernetes.tf b/tests/integration/update_cluster/minimal/kubernetes.tf
index 2096b241c7..91b5ff0e15 100644
--- a/tests/integration/update_cluster/minimal/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal_gossip/kubernetes.tf b/tests/integration/update_cluster/minimal_gossip/kubernetes.tf
index e05b124363..2dc45c43e7 100644
--- a/tests/integration/update_cluster/minimal_gossip/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal_gossip/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-k8s-local.cidr_block
   vpc_id                       = aws_vpc.minimal-k8s-local.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-k8s-local.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/minimal_gossip_irsa/kubernetes.tf b/tests/integration/update_cluster/minimal_gossip_irsa/kubernetes.tf
index 9b6f567149..584ee2d857 100644
--- a/tests/integration/update_cluster/minimal_gossip_irsa/kubernetes.tf
+++ b/tests/integration/update_cluster/minimal_gossip_irsa/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-k8s-local.cidr_block
   vpc_id                                             = aws_vpc.minimal-k8s-local.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-k8s-local.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/mixed_instances/kubernetes.tf b/tests/integration/update_cluster/mixed_instances/kubernetes.tf
index 75398ad671..c473a969d6 100644
--- a/tests/integration/update_cluster/mixed_instances/kubernetes.tf
+++ b/tests/integration/update_cluster/mixed_instances/kubernetes.tf
@@ -17,7 +17,7 @@ locals {
   vpc_cidr_block               = aws_vpc.mixedinstances-example-com.cidr_block
   vpc_id                       = aws_vpc.mixedinstances-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.mixedinstances-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -93,7 +93,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/mixed_instances_spot/kubernetes.tf b/tests/integration/update_cluster/mixed_instances_spot/kubernetes.tf
index 4fb9a2e2d2..0078007350 100644
--- a/tests/integration/update_cluster/mixed_instances_spot/kubernetes.tf
+++ b/tests/integration/update_cluster/mixed_instances_spot/kubernetes.tf
@@ -17,7 +17,7 @@ locals {
   vpc_cidr_block               = aws_vpc.mixedinstances-example-com.cidr_block
   vpc_id                       = aws_vpc.mixedinstances-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.mixedinstances-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -93,7 +93,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/nth-imds-processor-irsa/kubernetes.tf b/tests/integration/update_cluster/nth-imds-processor-irsa/kubernetes.tf
index dc828cb1e2..39d1cdaaa6 100644
--- a/tests/integration/update_cluster/nth-imds-processor-irsa/kubernetes.tf
+++ b/tests/integration/update_cluster/nth-imds-processor-irsa/kubernetes.tf
@@ -25,7 +25,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.nthimdsprocessor-longclustername-example-com.cidr_block
   vpc_id                                             = aws_vpc.nthimdsprocessor-longclustername-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.nthimdsprocessor-longclustername-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -133,7 +133,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/nth-imds-processor/kubernetes.tf b/tests/integration/update_cluster/nth-imds-processor/kubernetes.tf
index 0766d70351..295fa6b83b 100644
--- a/tests/integration/update_cluster/nth-imds-processor/kubernetes.tf
+++ b/tests/integration/update_cluster/nth-imds-processor/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.nthimdsprocessor-longclustername-example-com.cidr_block
   vpc_id                       = aws_vpc.nthimdsprocessor-longclustername-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.nthimdsprocessor-longclustername-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/nvidia/kubernetes.tf b/tests/integration/update_cluster/nvidia/kubernetes.tf
index f2b8221e96..7eadbe8102 100644
--- a/tests/integration/update_cluster/nvidia/kubernetes.tf
+++ b/tests/integration/update_cluster/nvidia/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = aws_vpc.minimal-example-com.cidr_block
   vpc_id                       = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block          = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/private-shared-ip/kubernetes.tf b/tests/integration/update_cluster/private-shared-ip/kubernetes.tf
index 8ab456787e..bc022810fb 100644
--- a/tests/integration/update_cluster/private-shared-ip/kubernetes.tf
+++ b/tests/integration/update_cluster/private-shared-ip/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = data.aws_vpc.private-shared-ip-example-com.cidr_block
   vpc_id                            = "vpc-12345678"
   vpc_ipv6_cidr_block               = data.aws_vpc.private-shared-ip-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/private-shared-subnet/kubernetes.tf b/tests/integration/update_cluster/private-shared-subnet/kubernetes.tf
index 9361faeb6b..ad2d391677 100644
--- a/tests/integration/update_cluster/private-shared-subnet/kubernetes.tf
+++ b/tests/integration/update_cluster/private-shared-subnet/kubernetes.tf
@@ -20,7 +20,7 @@ locals {
   vpc_cidr_block                = data.aws_vpc.private-shared-subnet-example-com.cidr_block
   vpc_id                        = "vpc-12345678"
   vpc_ipv6_cidr_block           = data.aws_vpc.private-shared-subnet-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length          = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length          = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -108,7 +108,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privatecalico/kubernetes.tf b/tests/integration/update_cluster/privatecalico/kubernetes.tf
index a34030e560..ccc3147f0f 100644
--- a/tests/integration/update_cluster/privatecalico/kubernetes.tf
+++ b/tests/integration/update_cluster/privatecalico/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privatecalico-example-com.cidr_block
   vpc_id                            = aws_vpc.privatecalico-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privatecalico-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privatecanal/kubernetes.tf b/tests/integration/update_cluster/privatecanal/kubernetes.tf
index 4b998ec474..71293608c4 100644
--- a/tests/integration/update_cluster/privatecanal/kubernetes.tf
+++ b/tests/integration/update_cluster/privatecanal/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privatecanal-example-com.cidr_block
   vpc_id                            = aws_vpc.privatecanal-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privatecanal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privatecilium-eni/kubernetes.tf b/tests/integration/update_cluster/privatecilium-eni/kubernetes.tf
index 44fb0b5670..7619a9f9d5 100644
--- a/tests/integration/update_cluster/privatecilium-eni/kubernetes.tf
+++ b/tests/integration/update_cluster/privatecilium-eni/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privatecilium-example-com.cidr_block
   vpc_id                            = aws_vpc.privatecilium-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privatecilium-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privatecilium/kubernetes.tf b/tests/integration/update_cluster/privatecilium/kubernetes.tf
index 44fb0b5670..7619a9f9d5 100644
--- a/tests/integration/update_cluster/privatecilium/kubernetes.tf
+++ b/tests/integration/update_cluster/privatecilium/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privatecilium-example-com.cidr_block
   vpc_id                            = aws_vpc.privatecilium-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privatecilium-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privatecilium2/kubernetes.tf b/tests/integration/update_cluster/privatecilium2/kubernetes.tf
index ceb897cb53..1dcdecca85 100644
--- a/tests/integration/update_cluster/privatecilium2/kubernetes.tf
+++ b/tests/integration/update_cluster/privatecilium2/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privatecilium-example-com.cidr_block
   vpc_id                            = aws_vpc.privatecilium-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privatecilium-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privateciliumadvanced/kubernetes.tf b/tests/integration/update_cluster/privateciliumadvanced/kubernetes.tf
index 69b08c0ab3..a222bd12e5 100644
--- a/tests/integration/update_cluster/privateciliumadvanced/kubernetes.tf
+++ b/tests/integration/update_cluster/privateciliumadvanced/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privateciliumadvanced-example-com.cidr_block
   vpc_id                            = aws_vpc.privateciliumadvanced-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privateciliumadvanced-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privatedns1/kubernetes.tf b/tests/integration/update_cluster/privatedns1/kubernetes.tf
index 535c7bb82d..aada82043d 100644
--- a/tests/integration/update_cluster/privatedns1/kubernetes.tf
+++ b/tests/integration/update_cluster/privatedns1/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privatedns1-example-com.cidr_block
   vpc_id                            = aws_vpc.privatedns1-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privatedns1-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privatedns2/kubernetes.tf b/tests/integration/update_cluster/privatedns2/kubernetes.tf
index 8ad545c62c..ed434bef72 100644
--- a/tests/integration/update_cluster/privatedns2/kubernetes.tf
+++ b/tests/integration/update_cluster/privatedns2/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = data.aws_vpc.privatedns2-example-com.cidr_block
   vpc_id                            = "vpc-12345678"
   vpc_ipv6_cidr_block               = data.aws_vpc.privatedns2-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privateflannel/kubernetes.tf b/tests/integration/update_cluster/privateflannel/kubernetes.tf
index e39094f81e..c7c785a1fb 100644
--- a/tests/integration/update_cluster/privateflannel/kubernetes.tf
+++ b/tests/integration/update_cluster/privateflannel/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privateflannel-example-com.cidr_block
   vpc_id                            = aws_vpc.privateflannel-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privateflannel-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privatekopeio/kubernetes.tf b/tests/integration/update_cluster/privatekopeio/kubernetes.tf
index 92c6b948d5..a1f072491b 100644
--- a/tests/integration/update_cluster/privatekopeio/kubernetes.tf
+++ b/tests/integration/update_cluster/privatekopeio/kubernetes.tf
@@ -24,7 +24,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privatekopeio-example-com.cidr_block
   vpc_id                            = aws_vpc.privatekopeio-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privatekopeio-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -128,7 +128,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/privateweave/kubernetes.tf b/tests/integration/update_cluster/privateweave/kubernetes.tf
index e451f344df..58b6b87030 100644
--- a/tests/integration/update_cluster/privateweave/kubernetes.tf
+++ b/tests/integration/update_cluster/privateweave/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                    = aws_vpc.privateweave-example-com.cidr_block
   vpc_id                            = aws_vpc.privateweave-example-com.id
   vpc_ipv6_cidr_block               = aws_vpc.privateweave-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/public-jwks-apiserver/kubernetes.tf b/tests/integration/update_cluster/public-jwks-apiserver/kubernetes.tf
index 75013043f4..38beb4c62b 100644
--- a/tests/integration/update_cluster/public-jwks-apiserver/kubernetes.tf
+++ b/tests/integration/update_cluster/public-jwks-apiserver/kubernetes.tf
@@ -23,7 +23,7 @@ locals {
   vpc_cidr_block                                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length                               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -123,7 +123,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/shared_subnet/kubernetes.tf b/tests/integration/update_cluster/shared_subnet/kubernetes.tf
index e48d42a1c7..9013f90f17 100644
--- a/tests/integration/update_cluster/shared_subnet/kubernetes.tf
+++ b/tests/integration/update_cluster/shared_subnet/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = data.aws_vpc.sharedsubnet-example-com.cidr_block
   vpc_id                       = "vpc-12345678"
   vpc_ipv6_cidr_block          = data.aws_vpc.sharedsubnet-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/shared_vpc/kubernetes.tf b/tests/integration/update_cluster/shared_vpc/kubernetes.tf
index ea20beea2e..3705d53461 100644
--- a/tests/integration/update_cluster/shared_vpc/kubernetes.tf
+++ b/tests/integration/update_cluster/shared_vpc/kubernetes.tf
@@ -15,7 +15,7 @@ locals {
   vpc_cidr_block               = data.aws_vpc.sharedvpc-example-com.cidr_block
   vpc_id                       = "vpc-12345678"
   vpc_ipv6_cidr_block          = data.aws_vpc.sharedvpc-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length         = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -83,7 +83,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/shared_vpc_ipv6/kubernetes.tf b/tests/integration/update_cluster/shared_vpc_ipv6/kubernetes.tf
index 3563fb1a93..f9697c57c1 100644
--- a/tests/integration/update_cluster/shared_vpc_ipv6/kubernetes.tf
+++ b/tests/integration/update_cluster/shared_vpc_ipv6/kubernetes.tf
@@ -22,7 +22,7 @@ locals {
   vpc_cidr_block                    = data.aws_vpc.minimal-ipv6-example-com.cidr_block
   vpc_id                            = "vpc-12345678"
   vpc_ipv6_cidr_block               = data.aws_vpc.minimal-ipv6-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length              = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -118,7 +118,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/unmanaged/kubernetes.tf b/tests/integration/update_cluster/unmanaged/kubernetes.tf
index a88c3c0d36..df6736d4d0 100644
--- a/tests/integration/update_cluster/unmanaged/kubernetes.tf
+++ b/tests/integration/update_cluster/unmanaged/kubernetes.tf
@@ -21,7 +21,7 @@ locals {
   vpc_cidr_block                = data.aws_vpc.unmanaged-example-com.cidr_block
   vpc_id                        = "vpc-12345678"
   vpc_ipv6_cidr_block           = data.aws_vpc.unmanaged-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length          = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length          = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "bastion_autoscaling_group_ids" {
@@ -113,7 +113,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/tests/integration/update_cluster/vfs-said/kubernetes.tf b/tests/integration/update_cluster/vfs-said/kubernetes.tf
index 762ce44802..13cdaec2c9 100644
--- a/tests/integration/update_cluster/vfs-said/kubernetes.tf
+++ b/tests/integration/update_cluster/vfs-said/kubernetes.tf
@@ -17,7 +17,7 @@ locals {
   vpc_cidr_block                     = aws_vpc.minimal-example-com.cidr_block
   vpc_id                             = aws_vpc.minimal-example-com.id
   vpc_ipv6_cidr_block                = aws_vpc.minimal-example-com.ipv6_cidr_block
-  vpc_ipv6_cidr_length               = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  vpc_ipv6_cidr_length               = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 output "cluster_name" {
@@ -93,7 +93,7 @@ output "vpc_ipv6_cidr_block" {
 }
 
 output "vpc_ipv6_cidr_length" {
-  value = local.vpc_ipv6_cidr_block == null ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
+  value = local.vpc_ipv6_cidr_block == "" ? null : tonumber(regex(".*/(\\d+)", local.vpc_ipv6_cidr_block)[0])
 }
 
 provider "aws" {
diff --git a/upup/pkg/fi/cloudup/awstasks/vpc.go b/upup/pkg/fi/cloudup/awstasks/vpc.go
index 8020c55c52..83d595cfe8 100644
--- a/upup/pkg/fi/cloudup/awstasks/vpc.go
+++ b/upup/pkg/fi/cloudup/awstasks/vpc.go
@@ -304,7 +304,7 @@ func (_ *VPC) RenderTerraform(t *terraform.TerraformTarget, a, e, changes *VPC)
 		cidrPrefixLengthCaptureList,
 		terraformWriter.LiteralFromIntValue(0),
 	)
-	if err := t.AddOutputVariable("vpc_ipv6_cidr_length", terraformWriter.LiteralNullConditionalExpression(
+	if err := t.AddOutputVariable("vpc_ipv6_cidr_length", terraformWriter.LiteralEmptyStrConditionalExpression(
 		terraformWriter.LiteralTokens("local", "vpc_ipv6_cidr_block"),
 		terraformWriter.LiteralFunctionExpression("tonumber", cidrPrefixLengthString),
 	)); err != nil {
diff --git a/upup/pkg/fi/cloudup/terraformWriter/literal.go b/upup/pkg/fi/cloudup/terraformWriter/literal.go
index a7add6210d..58bf92c9b2 100644
--- a/upup/pkg/fi/cloudup/terraformWriter/literal.go
+++ b/upup/pkg/fi/cloudup/terraformWriter/literal.go
@@ -140,13 +140,13 @@ func LiteralListExpression(args ...*Literal) *Literal {
 	}
 }
 
-// LiteralNullConditionalExpression constructs a Literal which returns `null`
-// if the supplied "nullable" expression is null, otherwise returns "value".
+// LiteralEmptyStrConditionalExpression constructs a Literal which returns `null`
+// if the supplied "empty" expression is an empty string, otherwise returns "value".
 // It is the caller's responsibility to ensure the supplied parameters do not use operators
 // with lower precedence than the conditional operator.
-func LiteralNullConditionalExpression(nullable, value *Literal) *Literal {
+func LiteralEmptyStrConditionalExpression(empty, value *Literal) *Literal {
 	return &Literal{
-		String: fmt.Sprintf("%s == null ? null : %s", nullable.String, value.String),
+		String: fmt.Sprintf("%s == \"\" ? null : %s", empty.String, value.String),
 	}
 }